Today there is work ongoing to provide different types of public warnings systems in order to, for example, introduce support for an Earthquake Tsunami Warning System (ETWS), enabling transmission of warning notifications about coming earthquakes and/or tsunamis through mobile stations. The ETWS warning notifications are divided into two types, a primary notification and a secondary notification.
The ETWS primary notification is sent in order to notify users about the most urgent event in seconds rather than minutes, such as imminent occurrence of an earthquake and the like. There are requirements to reach the users/mobile stations with an ETWS primary notification message within 4 seconds. In order to avoid that fake messages are received causing chaos, inclusion of authentication information in the primary notification will most likely be needed. An alternative to authenticate the information is to have authentication information in the form of a digital signature, e.g. 41 bytes if using Digital Signature Algorithm, DSA, signatures and/or the like.
The secondary notification is sent to give the users supplementary information that is of lesser urgency, such as instructions on what to do, where to get help, e.g. map to refuge facilities, time table of food distribution, and/or the like.
A Cell Broadcast Service (CBS) based solution has been envisaged for transmission of the ETWS warning notifications, wherein a ETWS message is broadcasted on control channel to all mobile stations within a cell.
Emergency messaging services aims to send warning messages only within affected areas. Also, for transmission of ETWS warning notifications within radio access network, for example, GSM EDGE Radio Access Network, GERAN, consists of notifying the users in idle mode through the broadcasted control channels that there is an ongoing warning. However, mobile stations that are not listening to the control channels in the macro networks would thus not receive the warning notifications that are sent in the macro networks while they are in, for example, Genericc Access Network, GAN, mode.
Similar problems exist in the case of different femtocell solutions, e.g. GSM, WCDMA, LTE Femto solutions and/or the like. These cells can also be deployed by the end users almost anywhere without interaction with the operator.